944 No Spark, No Tach Bounce
 

Hi, I have an '83 944 that has no spark and no tach bounce when the engine is turning over.

A few weeks ago, the car stalled while driving. After turning it over a few times, the car started back up and this continued to happen 3 or 4 more times, until it had no spark at all and died completely.

After reading other forums, I installed new reference and speed sensors. The reference sensor bracket didn't move when I changed them. Still no spark.
I then had the DME checked by the ECU Doctors in FL. They bench tested it and said it was fine, they also re-soldered some points. After I installed it, the car still wouldn't start.
I've checked the resistance on the coil. Primary test yielded .55 ohms, secondary yielded 6.5k ohms which I believe are within specs. When the ignition is on, there is no power to the coil.

I also bought a new DME relay.

The reference sensor connectors appear to be good, I don't see any cracking, but could this be the issue? Any other advice?

how were the speed/ref connectors and wiring?

all appear to be in good shape

If you still have no Tach bounce the reference sensors and not in correctly. It could easily be that the sensor mounting bracket is at fault, and check for other core problems (ie, connectors at the DME, flywheel stud, etc.) - something is wrong of course.

I agree with the others, double check your speed sensors. Give them a good clean and adjustment. I think I did mine and need to change one of leads.
They are located in a very tricky spot.
Also, check measurements at the connectors with a good quality multimeter. I had some interesting reading from a cheap nasty unit.. Someone posted a great thread on here detailing what colour and number and voltage they should be. I recall 9 and 23 had to be 600 ohms and the the outer two to be infinity or it could be the other way round.
All the best of luck, it can be frustrating fix.

Also check to be sure you plugged them in to the correct plug and didn't switch them.

Did you get to the bottom of this?

Similar problem here. Last week, it died....cranked fine... fuel was fine, no spark. Removed the positive terminal, replaced positive terminal....viola! it started & ran fine since...Today same issue, crank, no start, fuel ok, no tach bounce....tried the "reset"trick...nada. The only similarity between today & when this happened last was it's COLD, as in Ohio Winter COLD, less than 30º cold. Ideas please?

I'm trying to figure out a non start on my S.

One intermittant start issue I had with my NA was that the battery ground was corroded because the heater control valve had leaked on it.
What seemed to be the solution to that problem for a while was removing and reconnecting the battery terminal. Until I fried my DME.